I submitted a support ticket, but also found that it sends the receipt when the card is sent from a registered member but not when it's sent from an unregistered member.
I have the feeling that you're going to tell me that it's on purpose as it would make sense that potential spammers could then use the gallery to 'validate' email addresses? Am I right? What do I win?
If that is the case, is there any possibility of noting the receipt in the admin control panel? That way we could have notification without worrying about enabling spammers.